Drill for drilling metal



(No Model.) 4

' I v. PARKS.

DRILL FOR DRILLING METAL.

No. 516,277; Patented Mar; *13", "1 894.

m; NATIONAL umoangrmm courum wnm 1- UNITED STATES PATENT OFFICE.

VOLNEY PARKS, OF FORT WAYNE, INDIANA.

DRILL FOR DRILLING METAL.

SPECIFICATION forming part of Letters Patent No. 516,277, dated March 13, 1894.

Application filed 1111 17, 1893- To all whom it may concern.-

Be it known that I, VOLNEY PARKS, a citizen of the United States, residing at Fort Wayne, in the county of Allen and State of Indiana, have invented a new and useful Drill, of which the following is a specification.

The invention relates to improvements in drills.

The object of the present invention is to improve the construction of drills for metal hand boring, and to enable such boring to be efiected with greater rapidity and more ease than heretofore.

The invention consists in the construction and novel combination and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings and pointed out in the claim hereto appended.

In the drawings-Figure 1 is a perspective view of a drill constructed in accordance with this invention. Fig. 2 is a longitudinal sectional view. Fig. 3 is a plan view of the end of the drill. Fig. 4 is a transverse sectional view.

Like numerals of reference indicate corresponding parts in all the figures of the drawin s.

I designates a drill, designed to be used in a brace for boring metals by hand, or otherwise, and provided at its engaging end with a central cylindrical recess or socket 2, and having in its sides longitudinal grooves 3 and 4 forming end cutting edges. The engaging end of the drill is beveled at opposite sides of the opening or socket 2 in forming the cutting edges. The central opening or socket 2 in boring leaves a core of metal, and does away with the usual central point, thereby greatly increasing the rapidity of drilling as the metal is drilled around the core, and at the same time greatly lessening the pressure required for drilling. The grooves 3 and 4 communicate at their outer ends with the opening or socket 2; and the groove 3 is of suflicient depth to merge into the opening or socket 2 at the lower end of the latter to enable the core of metal, which is broken ofi by or during the drilling, to pass out by means Serial No. 477,982. (No model.)

of the groove 3 without obstructing or interfering with theoperation of drilling. By arranging the cutting edges at the sides of the central opening or socket they move in a curved path, and are more effective, and have the greater amount of movement than a drilling point, whichis usually located at the'center of the engaging end of the drill.

It will be seen that the drill greatly facilitates and increases the rapidity of metal boring, and enables the same to be effectively and conveniently performed by hand, that in I drilling a hole the actual cutting of metal is lessened, and that the central point which necessitates so much pressure in ordinary drilling is dispensed with. It will also be apparent that the core of metal, which is left, will break off during the operation of drilling, and will pass out of the hole through one of the grooves without interfering with or obstructing the operation of drilling.

The grooves 3 and 4, which may if desired be of a greater number, are slightly inclined to give them a slight twist.

Changes in the form, proportion and the minor details of construction may be resorted to without departing from the principle or sacrificing any of the advantages of this invention.

What I claim is- A drill provided at its ends with a central opening or socket and having longitudinal 8o grooves forming cutting edges at the sides of the socket or opening, one of the grooves being of suiiicient depth to communicate with the socket at the base or inner end thereof to allow the core formed by the opening or socket 8 5 in boring to pass out without interfering with or obstructing the operation of drilling, substantially as described.

In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence 'of two witnesses.

VOLNEY PAR-KS. 

